1. Technical Field
The present disclosure relates to a nozzle, an image forming apparatus including the nozzle, and a method of deriving powder.
2. Description of Related Art
A nozzle equipped with a screw mechanism for transporting powder is known. The screw mechanism derives powder out of a powder container. Powder generally receives mechanical pressure from the screw mechanism during the transportation and therefore gets aggregated to undesirably produce coarse particles. JP-2001-166581-A describes a nozzle capable of deriving powder out of a powder container without screw mechanism.
This nozzle transports toner particles (i.e., a powder) from inside to outside of a toner cartridge (i.e., a powder container) by introducing the air into the toner cartridge. Toner particles do not receive mechanical pressure during the transportation and therefore they are suppressed from getting aggregated to undesirably produce coarse particles. However, toner particles may possibly get aggregated and undesirably produce coarse particles by the effect of temperature and humidity.
JP-2006-23782-A describes a method of removing coarse particles from toner by means of sieving. Coarse particles are removed by sieving toner with a filter vibrated by ultrasonic waves. However, there is a concern that the apertures of the filter are clogged with toner particles softened by frictional heat generated due to vibration of the filter, or another concern that the apertures of the filter are enlarged by stress caused by vibration of the filter.
JP-2009-90167-A describes a sieve device having a rotation shaft, a cylindrical sieve disposed coaxially with the rotation shaft, and rotary blades attached to the rotation shaft. Further, this sieve device has a mechanism of transporting powder from inside to outside of the cylindrical sieve. Thus, the powder is sieved only by rotating the rotary blades without vibrating the sieve.
In some cases, nozzles are limited in size because they are generally used being connected to powder containers. Because the mechanism of transporting powder from inside to outside of the cylindrical sieve requires a large space for collecting powders passed through the sieve, when this sieve device is installed in a nozzle, the nozzle gets undesirably large in size.